Are fasteners required for installation? Can it be installed on the ceiling ?

Update:Jan 13,2022
Summary:This plastic access panel can be installed using mastic to adhere it to the wall or ceiling. No need to use any fasteners.It can be used in a wall or ......
This plastic access panel can be installed using mastic to adhere it to the wall or ceiling. No need to use any fasteners.
It can be used in a wall or ceiling. No difference .